油气两相压降数值试井模型及其典型曲线的规律

提出油气两相流动压降试井数字模型的数值解法，用此解法对均质油藏中油气两相流动试井的规律进行了研究，根据实例计算结果，分析油气两相流下典型压降试井曲线的特征，以及油、气的初始饱和度分布，两相黏度比，饱和度梯度、相对渗透率关系对试井曲线的影响和相应的作用机理，首次发现气体的存在会使油气两相试井的压力导数曲线表现出类似于单相流双重介质试井的压力导数曲线的“下凹”特征。

Numerical model of oil-gas flow draw-down test and its typical curve's characteristics

The paper presents the idea to solve the model of the oil gas flow well testing numerically. The model is used then to analyze the characteristics of oil gas flow in homogeneous reservoir. Through the solution of examples, the paper gives the characteristics of a typical drawdown type curve of oil gas flow, shows how the initial saturation, the viscosity ratio of oil to gas, the saturation gradient and the relative permeability relationship affect the well testing curves, and answers why the above factors can do so. Though different reasons bring different results, there is a common point that: the presence of gas in reservoir induces a trough immediate after the hump on the derive curve. This novel point can surely improve the knowledge of multi phase well testing.